A huge 1Kg of Espresso Crema Ground Coffee for just £6.37 delivered (with Prime) from Amazon.
Nice to store too, as it's dispatched as 4 x 250g bags, so you can keep your coffee fresher.
Decent reviews (for this particular version of the Happy Belly brand), I've had a good look through the reviews and this one seems favourable.
One of the cheapest 1KG of coffee you can get, especially delivered if you're with Amazon.
I've taken a punt, hopefully it'll do the trick for ice coffees and I'll be using it with the Aeropress (which I've read produces best results with this).